Design of Pressure Vessel using PV Elite – Fabrication aspects of Pressure Vessel

A: PV Elite calculates the minimum required thickness of pressure vessel shells based on internal pressure, material allowable stresses, corrosion allowance, and external loads per design codes like ASME Section VIII. It considers the fabrication constraints such as rolling limits and available plate sizes. By iteratively adjusting input parameters, engineers can optimize shell thickness to avoid overdesign, which reduces material waste and fabrication cost while maintaining safety. PV Elite also evaluates the stresses and checks for local and global failures, ensuring the selected thickness meets both code and fabrication feasibility. More details can be found in the PV Elite documentation: https://hexagonppm.com/resources.

A: Weld joints are critical to the structural integrity of pressure vessels since they are the points where two components are joined, often subjected to high stress. PV Elite allows you to define different weld joint types and evaluates their impact on stress distribution and allowable stresses per relevant codes. It helps identify critical weld areas that require special inspection such as radiography or ultrasonic testing. Furthermore, PV Elite incorporates factors like weld joint efficiency, which affects the required thickness and overall strength of the vessel components. This ensures that fabrication detail complies with design requirements, minimizing the risk of failure. For further reading on weld joints and joint efficiency, see ASME BPVC Section VIII Division 1.

A: Corrosion allowance is a deliberate additional thickness added to the pressure vessel components to account for material loss over the vessel’s operational life due to corrosion. In PV Elite, you specify the corrosion allowance, and the software includes this in the minimum required thickness calculation ensuring that after expected corrosion, the vessel maintains structural integrity and safety. This is crucial in fabrication phase to select the correct plate thickness and welding procedures since it impacts both material cost and fabrication complexity. Typically, corrosion allowance values are chosen based on the process fluid, operating environment, and maintenance practices. More detailed guidelines can be found in industry standards such as ASME Section VIII.

A: Yes, PV Elite aids engineers in verifying dimensional checks and fabrication tolerances to ensure that the constructed pressure vessel complies with design parameters. While it primarily focuses on structural analysis and design code compliance, it allows users to input dimensional data as per fabrication standards and highlights discrepancies if they affect vessel integrity or code compliance. This helps fabricators maintain quality control and avoid costly rework. For detailed tolerance guidelines, refer to ASME Section VIII and fabrication quality manuals like those from The American Society of Mechanical Engineers.

A: During fabrication design, PV Elite considers external loads such as wind, seismic loads, weight of attachments (lifting lugs, nozzles), and operating loads including thermal stresses. These loads influence vessel support design, saddle or skirt sizing, and shell reinforcement requirements. Inputting accurate external loads allows PV Elite to simulate combined stress scenarios ensuring that the pressure vessel will remain safe and functional not only under internal pressure but also under these additional loads experienced during fabrication, transportation, and operation. Detailed methods for load application can be found in ASME Section VIII Division 2 and related structural standards.

A: Heat treatment processes such as post-weld heat treatment (PWHT) relieve residual stresses developed during welding, thereby improving the mechanical properties like toughness and ductility of the vessel material. Although PV Elite does not perform heat treatment simulation, it allows designers to incorporate material properties after heat treatment into calculations, ensuring stresses and allowable limits reflect the actual conditions. This affects the choice of materials, welding procedures, and fabrication scheduling. Fabrication standards and ASME Section VIII provide guidelines on when and how heat treatments should be applied.

A: Inspection and testing during fabrication are vital to ensure the pressure vessel meets safety and quality standards. Designers using PV Elite factor in weld joint types, material selection, and fabrication complexity to determine required non-destructive examination (NDE) methods like radiography, ultrasonic testing, magnetic particle inspection, and hydrostatic testing. PV Elite's detailed code compliance reporting assists in verifying that inspection requirements are accounted for. Understanding these helps coordinate fabrication schedules and cost estimation. For comprehensive inspection requirements, ASME BPVC Section V and VIII provide detailed protocols.

A: Nozzle reinforcements are areas around openings for connections, designed to maintain pressure boundary integrity despite the discontinuities caused by the openings. During fabrication, these reinforcements can involve additional thickness or separate reinforcement pads. PV Elite calculates the required reinforcement based on nozzle size, loading conditions, and applicable code rules, ensuring the nozzle junction meets strength requirements. This impacts fabrication effort since reinforcements may require additional material, welding, and inspection. Detailed nozzle reinforcement design is governed by ASME Section VIII Division 1, and PV Elite provides specific features to handle these calculations.

A: Indeed, PV Elite includes features to generate detailed design and calculation reports that conform to ASME and other relevant codes. These reports include fabrication details such as component thicknesses, weld joint efficiencies, allowable stresses, corrosion allowances, reinforcement calculations, and stress analysis results. These documents are essential for fabrication shops, quality control, and certification bodies. Utilizing the built-in reporting features helps reduce errors, speeds up the review process, and ensures traceability. More information on report generation can be found in the PV Elite user documentation available at https://hexagonppm.com/products/pv-elite.